diff options
Diffstat (limited to 'kernel/auditsc.c')
| -rw-r--r-- | kernel/auditsc.c | 834 |
1 files changed, 434 insertions, 400 deletions
diff --git a/kernel/auditsc.c b/kernel/auditsc.c index c4394ab..7f160df 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -2,6 +2,8 @@ * Handles all system-call specific auditing features. * * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina. + * Copyright 2005 Hewlett-Packard Development Company, L.P. + * Copyright (C) 2005 IBM Corporation * All Rights Reserved. * * This program is free software; you can redistribute it and/or modify @@ -27,11 +29,22 @@ * this file -- see entry.S) is based on a GPL'd patch written by * okir@suse.de and Copyright 2003 SuSE Linux AG. * + * The support of additional filter rules compares (>, <, >=, <=) was + * added by Dustin Kirkland <dustin.kirkland@us.ibm.com>, 2005. + * + * Modified by Amy Griffis <amy.griffis@hp.com> to collect additional + * filesystem information. + * + * Subject and object context labeling support added by <danjones@us.ibm.com> + * and <dustin.kirkland@us.ibm.com> for LSPP certification compliance. */ #include <linux/init.h> #include <asm/types.h> #include <asm/atomic.h> +#include <asm/types.h> +#include <linux/fs.h> +#include <linux/namei.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/mount.h> @@ -39,16 +52,16 @@ #include <linux/audit.h> #include <linux/personality.h> #include <linux/time.h> -#include <linux/kthread.h> #include <linux/netlink.h> #include <linux/compiler.h> #include <asm/unistd.h> +#include <linux/security.h> +#include <linux/list.h> +#include <linux/tty.h> + +#include "audit.h" -/* 0 = no checking - 1 = put_count checking - 2 = verbose put_count checking -*/ -#define AUDIT_DEBUG 0 +extern struct list_head audit_filter_list[]; /* No syscall auditing will take place unless audit_enabled != 0. */ extern int audit_enabled; @@ -62,29 +75,6 @@ extern int audit_enabled; * path_lookup. */ #define AUDIT_NAMES_RESERVED 7 -/* At task start time, the audit_state is set in the audit_context using - a per-task filter. At syscall entry, the audit_state is augmented by - the syscall filter. */ -enum audit_state { - AUDIT_DISABLED, /* Do not create per-task audit_context. - * No syscall-specific audit records can - * be generated. */ - AUDIT_SETUP_CONTEXT, /* Create the per-task audit_context, - * but don't necessarily fill it in at - * syscall entry time (i.e., filter - * instead). */ - AUDIT_BUILD_CONTEXT, /* Create the per-task audit_context, - * and always fill it in at syscall - * entry time. This makes a full - * syscall record available if some - * other part of the kernel decides it - * should be recorded. */ - AUDIT_RECORD_CONTEXT /* Create the per-task audit_context, - * always fill it in at syscall entry - * time, and always write out the audit - * record at syscall exit time. */ -}; - /* When fs/namei.c:getname() is called, we store the pointer in name and * we don't let putname() free it (instead we free all of the saved * pointers at syscall exit time). @@ -93,12 +83,13 @@ enum audit_state { struct audit_names { const char *name; unsigned long ino; + unsigned long pino; dev_t dev; umode_t mode; uid_t uid; gid_t gid; dev_t rdev; - unsigned flags; + char *ctx; }; struct audit_aux_data { @@ -115,6 +106,7 @@ struct audit_aux_data_ipcctl { uid_t uid; gid_t gid; mode_t mode; + char *ctx; }; struct audit_aux_data_socketcall { @@ -167,290 +159,72 @@ struct audit_context { #endif }; - /* Public API */ -/* There are three lists of rules -- one to search at task creation - * time, one to search at syscall entry time, and another to search at - * syscall exit time. */ -static struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { - LIST_HEAD_INIT(audit_filter_list[0]), - LIST_HEAD_INIT(audit_filter_list[1]), - LIST_HEAD_INIT(audit_filter_list[2]), - LIST_HEAD_INIT(audit_filter_list[3]), - LIST_HEAD_INIT(audit_filter_list[4]), -#if AUDIT_NR_FILTERS != 5 -#error Fix audit_filter_list initialiser -#endif -}; - -struct audit_entry { - struct list_head list; - struct rcu_head rcu; - struct audit_rule rule; -}; - -extern int audit_pid; - -/* Copy rule from user-space to kernel-space. Called from - * audit_add_rule during AUDIT_ADD. */ -static inline int audit_copy_rule(struct audit_rule *d, struct audit_rule *s) -{ - int i; - - if (s->action != AUDIT_NEVER - && s->action != AUDIT_POSSIBLE - && s->action != AUDIT_ALWAYS) - return -1; - if (s->field_count < 0 || s->field_count > AUDIT_MAX_FIELDS) - return -1; - if ((s->flags & ~AUDIT_FILTER_PREPEND) >= AUDIT_NR_FILTERS) - return -1; - - d->flags = s->flags; - d->action = s->action; - d->field_count = s->field_count; - for (i = 0; i < d->field_count; i++) { - d->fields[i] = s->fields[i]; - d->values[i] = s->values[i]; - } - for (i = 0; i < AUDIT_BITMASK_SIZE; i++) d->mask[i] = s->mask[i]; - return 0; -} - -/* Check to see if two rules are identical. It is called from - * audit_add_rule during AUDIT_ADD and - * audit_del_rule during AUDIT_DEL. */ -static inline int audit_compare_rule(struct audit_rule *a, struct audit_rule *b) -{ - int i; - - if (a->flags != b->flags) - return 1; - - if (a->action != b->action) - return 1; - - if (a->field_count != b->field_count) - return 1; - - for (i = 0; i < a->field_count; i++) { - if (a->fields[i] != b->fields[i] - || a->values[i] != b->values[i]) - return 1; - } - - for (i = 0; i < AUDIT_BITMASK_SIZE; i++) - if (a->mask[i] != b->mask[i]) - return 1; - - return 0; -} - -/* Note that audit_add_rule and audit_del_rule are called via - * audit_receive() in audit.c, and are protected by - * audit_netlink_sem. */ -static inline int audit_add_rule(struct audit_rule *rule, - struct list_head *list) -{ - struct audit_entry *entry; - - /* Do not use the _rcu iterator here, since this is the only - * addition routine. */ - list_for_each_entry(entry, list, list) { - if (!audit_compare_rule(rule, &entry->rule)) { - return -EEXIST; - } - } - - if (!(entry = kmalloc(sizeof(*entry), GFP_KERNEL))) - return -ENOMEM; - if (audit_copy_rule(&entry->rule, rule)) { - kfree(entry); - return -EINVAL; - } - - if (entry->rule.flags & AUDIT_FILTER_PREPEND) { - entry->rule.flags &= ~AUDIT_FILTER_PREPEND; - list_add_rcu(&entry->list, list); - } else { - list_add_tail_rcu(&entry->list, list); - } - - return 0; -} - -static inline void audit_free_rule(struct rcu_head *head) -{ - struct audit_entry *e = container_of(head, struct audit_entry, rcu); - kfree(e); -} - -/* Note that audit_add_rule and audit_del_rule are called via - * audit_receive() in audit.c, and are protected by - * audit_netlink_sem. */ -static inline int audit_del_rule(struct audit_rule *rule, - struct list_head *list) -{ - struct audit_entry *e; - - /* Do not use the _rcu iterator here, since this is the only - * deletion routine. */ - list_for_each_entry(e, list, list) { - if (!audit_compare_rule(rule, &e->rule)) { - list_del_rcu(&e->list); - call_rcu(&e->rcu, audit_free_rule); - return 0; - } - } - return -ENOENT; /* No matching rule */ -} - -static int audit_list_rules(void *_dest) -{ - int pid, seq; - int *dest = _dest; - struct audit_entry *entry; - int i; - - pid = dest[0]; - seq = dest[1]; - kfree(dest); - - down(&audit_netlink_sem); - - /* The *_rcu iterators not needed here because we are - always called with audit_netlink_sem held. */ - for (i=0; i<AUDIT_NR_FILTERS; i++) { - list_for_each_entry(entry, &audit_filter_list[i], list) - audit_send_reply(pid, seq, AUDIT_LIST, 0, 1, - &entry->rule, sizeof(entry->rule)); - } - audit_send_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); - - up(&audit_netlink_sem); - return 0; -} - -int audit_receive_filter(int type, int pid, int uid, int seq, void *data, - uid_t loginuid) -{ - struct task_struct *tsk; - int *dest; - int err = 0; - unsigned listnr; - - switch (type) { - case AUDIT_LIST: - /* We can't just spew out the rules here because we might fill - * the available socket buffer space and deadlock waiting for - * auditctl to read from it... which isn't ever going to - * happen if we're actually running in the context of auditctl - * trying to _send_ the stuff */ - - dest = kmalloc(2 * sizeof(int), GFP_KERNEL); - if (!dest) - return -ENOMEM; - dest[0] = pid; - dest[1] = seq; - - tsk = kthread_run(audit_list_rules, dest, "audit_list_rules"); - if (IS_ERR(tsk)) { - kfree(dest); - err = PTR_ERR(tsk); - } - break; - case AUDIT_ADD: - listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND; - if (listnr >= AUDIT_NR_FILTERS) - return -EINVAL; - - err = audit_add_rule(data, &audit_filter_list[listnr]); - if (!err) - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "auid=%u added an audit rule\n", loginuid); - break; - case AUDIT_DEL: - listnr =((struct audit_rule *)data)->flags & ~AUDIT_FILTER_PREPEND; - if (listnr >= AUDIT_NR_FILTERS) - return -EINVAL; - - err = audit_del_rule(data, &audit_filter_list[listnr]); - if (!err) - audit_log(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE, - "auid=%u removed an audit rule\n", loginuid); - break; - default: - return -EINVAL; - } - - return err; -} /* Compare a task_struct with an audit_rule. Return 1 on match, 0 * otherwise. */ static int audit_filter_rules(struct task_struct *tsk, - struct audit_rule *rule, + struct audit_krule *rule, struct audit_context *ctx, enum audit_state *state) { int i, j; for (i = 0; i < rule->field_count; i++) { - u32 field = rule->fields[i] & ~AUDIT_NEGATE; - u32 value = rule->values[i]; + struct audit_field *f = &rule->fields[i]; int result = 0; - switch (field) { + switch (f->type) { case AUDIT_PID: - result = (tsk->pid == value); + result = audit_comparator(tsk->pid, f->op, f->val); break; case AUDIT_UID: - result = (tsk->uid == value); + result = audit_comparator(tsk->uid, f->op, f->val); break; case AUDIT_EUID: - result = (tsk->euid == value); + result = audit_comparator(tsk->euid, f->op, f->val); break; case AUDIT_SUID: - result = (tsk->suid == value); + result = audit_comparator(tsk->suid, f->op, f->val); break; case AUDIT_FSUID: - result = (tsk->fsuid == value); + result = audit_comparator(tsk->fsuid, f->op, f->val); break; case AUDIT_GID: - result = (tsk->gid == value); + result = audit_comparator(tsk->gid, f->op, f->val); break; case AUDIT_EGID: - result = (tsk->egid == value); + result = audit_comparator(tsk->egid, f->op, f->val); break; case AUDIT_SGID: - result = (tsk->sgid == value); + result = audit_comparator(tsk->sgid, f->op, f->val); break; case AUDIT_FSGID: - result = (tsk->fsgid == value); + result = audit_comparator(tsk->fsgid, f->op, f->val); break; case AUDIT_PERS: - result = (tsk->personality == value); + result = audit_comparator(tsk->personality, f->op, f->val); break; case AUDIT_ARCH: - if (ctx) - result = (ctx->arch == value); + if (ctx) + result = audit_comparator(ctx->arch, f->op, f->val); break; case AUDIT_EXIT: if (ctx && ctx->return_valid) - result = (ctx->return_code == value); + result = audit_comparator(ctx->return_code, f->op, f->val); break; case AUDIT_SUCCESS: if (ctx && ctx->return_valid) { - if (value) - result = (ctx->return_valid == AUDITSC_SUCCESS); + if (f->val) + result = audit_comparator(ctx->return_valid, f->op, AUDITSC_SUCCESS); else - result = (ctx->return_valid == AUDITSC_FAILURE); + result = audit_comparator(ctx->return_valid, f->op, AUDITSC_FAILURE); } break; case AUDIT_DEVMAJOR: if (ctx) { for (j = 0; j < ctx->name_count; j++) { - if (MAJOR(ctx->names[j].dev)==value) { + if (audit_comparator(MAJOR(ctx->names[j].dev), f->op, f->val)) { ++result; break; } @@ -460,7 +234,7 @@ static int audit_filter_rules(struct task_struct *tsk, case AUDIT_DEVMINOR: if (ctx) { for (j = 0; j < ctx->name_count; j++) { - if (MINOR(ctx->names[j].dev)==value) { + if (audit_comparator(MINOR(ctx->names[j].dev), f->op, f->val)) { ++result; break; } @@ -470,7 +244,8 @@ static int audit_filter_rules(struct task_struct *tsk, case AUDIT_INODE: if (ctx) { for (j = 0; j < ctx->name_count; j++) { - if (ctx->names[j].ino == value) { + if (audit_comparator(ctx->names[j].ino, f->op, f->val) || + audit_comparator(ctx->names[j].pino, f->op, f->val)) { ++result; break; } @@ -480,19 +255,17 @@ static int audit_filter_rules(struct task_struct *tsk, case AUDIT_LOGINUID: result = 0; if (ctx) - result = (ctx->loginuid == value); + result = audit_comparator(ctx->loginuid, f->op, f->val); break; case AUDIT_ARG0: case AUDIT_ARG1: case AUDIT_ARG2: case AUDIT_ARG3: if (ctx) - result = (ctx->argv[field-AUDIT_ARG0]==value); + result = audit_comparator(ctx->argv[f->type-AUDIT_ARG0], f->op, f->val); break; } - if (rule->fields[i] & AUDIT_NEGATE) - result = !result; if (!result) return 0; } @@ -527,7 +300,7 @@ static enum audit_state audit_filter_task(struct task_struct *tsk) /* At syscall entry and exit time, this filter is called if the * audit_state is not low enough that auditing cannot take place, but is * also not high enough that we already know we have to write an audit - * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). + * record (i.e., the state is AUDIT_SETUP_CONTEXT or AUDIT_BUILD_CONTEXT). */ static enum audit_state audit_filter_syscall(struct task_struct *tsk, struct audit_context *ctx, @@ -541,77 +314,19 @@ static enum audit_state audit_filter_syscall(struct task_struct *tsk, rcu_read_lock(); if (!list_empty(list)) { - int word = AUDIT_WORD(ctx->major); - int bit = AUDIT_BIT(ctx->major); - - list_for_each_entry_rcu(e, list, list) { - if ((e->rule.mask[word] & bit) == bit - && audit_filter_rules(tsk, &e->rule, ctx, &state)) { - rcu_read_unlock(); - return state; - } - } - } - rcu_read_unlock(); - return AUDIT_BUILD_CONTEXT; -} - -static int audit_filter_user_rules(struct netlink_skb_parms *cb, - struct audit_rule *rule, - enum audit_state *state) -{ - int i; - - for (i = 0; i < rule->field_count; i++) { - u32 field = rule->fields[i] & ~AUDIT_NEGATE; - u32 value = rule->values[i]; - int result = 0; - - switch (field) { - case AUDIT_PID: - result = (cb->creds.pid == value); - break; - case AUDIT_UID: - result = (cb->creds.uid == value); - break; - case AUDIT_GID: - result = (cb->creds.gid == value); - break; - case AUDIT_LOGINUID: - result = (cb->loginuid == value); - break; - } - - if (rule->fields[i] & AUDIT_NEGATE) - result = !result; - if (!result) - return 0; - } - switch (rule->action) { - case AUDIT_NEVER: *state = AUDIT_DISABLED; break; - case AUDIT_POSSIBLE: *state = AUDIT_BUILD_CONTEXT; break; - case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; - } - return 1; -} - -int audit_filter_user(struct netlink_skb_parms *cb, int type) -{ - struct audit_entry *e; - enum audit_state state; - int ret = 1; - - rcu_read_lock(); - list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { - if (audit_filter_user_rules(cb, &e->rule, &state)) { - if (state == AUDIT_DISABLED) - ret = 0; - break; + int word = AUDIT_WORD(ctx->major); + int bit = AUDIT_BIT(ctx->major); + + list_for_each_entry_rcu(e, list, list) { + if ((e->rule.mask[word] & bit) == bit + && audit_filter_rules(tsk, &e->rule, ctx, &state)) { + rcu_read_unlock(); + return state; + } } } rcu_read_unlock(); - - return ret; /* Audit by default */ + return AUDIT_BUILD_CONTEXT; } /* This should be called with task_lock() held. */ @@ -654,17 +369,18 @@ static inline void audit_free_names(struct audit_context *context) #if AUDIT_DEBUG == 2 if (context->auditable ||context->put_count + context->ino_count != context->name_count) { - printk(KERN_ERR "audit.c:%d(:%d): major=%d in_syscall=%d" + printk(KERN_ERR "%s:%d(:%d): major=%d in_syscall=%d" " name_count=%d put_count=%d" " ino_count=%d [NOT freeing]\n", - __LINE__, + __FILE__, __LINE__, context->serial, context->major, context->in_syscall, context->name_count, context->put_count, context->ino_count); - for (i = 0; i < context->name_count; i++) + for (i = 0; i < context->name_count; i++) { printk(KERN_ERR "names[%d] = %p = %s\n", i, context->names[i].name, - context->names[i].name); + context->names[i].name ?: "(null)"); + } dump_stack(); return; } @@ -674,9 +390,13 @@ static inline void audit_free_names(struct audit_context *context) context->ino_count = 0; #endif - for (i = 0; i < context->name_count; i++) + for (i = 0; i < context->name_count; i++) { + char *p = context->names[i].ctx; + context->names[i].ctx = NULL; + kfree(p); if (context->names[i].name) __putname(context->names[i].name); + } context->name_count = 0; if (context->pwd) dput(context->pwd); @@ -696,6 +416,12 @@ static inline void audit_free_aux(struct audit_context *context) dput(axi->dentry); mntput(axi->mnt); } + if ( aux->type == AUDIT_IPC ) { + struct audit_aux_data_ipcctl *axi = (void *)aux; + if (axi->ctx) + kfree(axi->ctx); + } + context->aux = aux->next; kfree(aux); } @@ -721,10 +447,15 @@ static inline struct audit_context *audit_alloc_context(enum audit_state state) return context; } -/* Filter on the task information and allocate a per-task audit context +/** + * audit_alloc - allocate an audit context block for a task + * @tsk: task + * + * Filter on the task information and allocate a per-task audit context * if necessary. Doing so turns on system call auditing for the * specified task. This is called from copy_process, so no lock is - * needed. */ + * needed. + */ int audit_alloc(struct task_struct *tsk) { struct audit_context *context; @@ -775,7 +506,37 @@ static inline void audit_free_context(struct audit_context *context) printk(KERN_ERR "audit: freed %d contexts\n", count); } -static void audit_log_task_info(struct audit_buffer *ab) +static void audit_log_task_context(struct audit_buffer *ab, gfp_t gfp_mask) +{ + char *ctx = NULL; + ssize_t len = 0; + + len = security_getprocattr(current, "current", NULL, 0); + if (len < 0) { + if (len != -EINVAL) + goto error_path; + return; + } + + ctx = kmalloc(len, gfp_mask); + if (!ctx) + goto error_path; + + len = security_getprocattr(current, "current", ctx, len); + if (len < 0 ) + goto error_path; + + audit_log_format(ab, " subj=%s", ctx); + return; + +error_path: + if (ctx) + kfree(ctx); + audit_panic("error in audit_log_task_context"); + return; +} + +static void audit_log_task_info(struct audit_buffer *ab, gfp_t gfp_mask) { char name[sizeof(current->comm)]; struct mm_struct *mm = current->mm; @@ -788,6 +549,10 @@ static void audit_log_task_info(struct audit_buffer *ab) if (!mm) return; + /* + * this is brittle; all callers that pass GFP_ATOMIC will have + * NULL current->mm and we won't get here. + */ down_read(&mm->mmap_sem); vma = mm->mmap; while (vma) { @@ -801,6 +566,7 @@ static void audit_log_task_info(struct audit_buffer *ab) vma = vma->vm_next; } up_read(&mm->mmap_sem); + audit_log_task_context(ab, gfp_mask); } static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) @@ -808,6 +574,7 @@ static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) int i; struct audit_buffer *ab; struct audit_aux_data *aux; + const char *tty; ab = audit_log_start(context, gfp_mask, AUDIT_SYSCALL); if (!ab) @@ -820,11 +587,15 @@ static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) audit_log_format(ab, " success=%s exit=%ld", (context->return_valid==AUDITSC_SUCCESS)?"yes":"no", context->return_code); + if (current->signal->tty && current->signal->tty->name) + tty = current->signal->tty->name; + else + tty = "(none)"; audit_log_format(ab, " a0=%lx a1=%lx a2=%lx a3=%lx items=%d" " pid=%d auid=%u uid=%u gid=%u" " euid=%u suid=%u fsuid=%u" - " egid=%u sgid=%u fsgid=%u", + " egid=%u sgid=%u fsgid=%u tty=%s", context->argv[0], context->argv[1], context->argv[2], @@ -835,8 +606,8 @@ static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) context->uid, context->gid, context->euid, context->suid, context->fsuid, - context->egid, context->sgid, context->fsgid); - audit_log_task_info(ab); + context->egid, context->sgid, context->fsgid, tty); + audit_log_task_info(ab, gfp_mask); audit_log_end(ab); for (aux = context->aux; aux; aux = aux->next) { @@ -849,8 +620,8 @@ static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) case AUDIT_IPC: { struct audit_aux_data_ipcctl *axi = (void *)aux; audit_log_format(ab, - " qbytes=%lx iuid=%u igid=%u mode=%x", - axi->qbytes, axi->uid, axi->gid, axi->mode); + " qbytes=%lx iuid=%u igid=%u mode=%x obj=%s", + axi->qbytes, axi->uid, axi->gid, axi->mode, axi->ctx); break; } case AUDIT_SOCKETCALL: { @@ -885,42 +656,62 @@ static void audit_log_exit(struct audit_context *context, gfp_t gfp_mask) } } for (i = 0; i < context->name_count; i++) { + unsigned long ino = context->names[i].ino; + unsigned long pino = context->names[i].pino; + ab = audit_log_start(context, gfp_mask, AUDIT_PATH); if (!ab) continue; /* audit_panic has been called */ audit_log_format(ab, "item=%d", i); - if (context->names[i].name) { - audit_log_format(ab, " name="); + + audit_log_format(ab, " name="); + if (context->names[i].name) audit_log_untrustedstring(ab, context->names[i].name); - } - audit_log_format(ab, " flags=%x\n", context->names[i].flags); - - if (context->names[i].ino != (unsigned long)-1) - audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#o" - " ouid=%u ogid=%u rdev=%02x:%02x", - context->names[i].ino, - MAJOR(context->names[i].dev), - MINOR(context->names[i].dev), - context->names[i].mode, - context->names[i].uid, - context->names[i].gid, - MAJOR(context->names[i].rdev), + else + audit_log_format(ab, "(null)"); + + if (pino != (unsigned long)-1) + audit_log_format(ab, " parent=%lu", pino); + if (ino != (unsigned long)-1) + audit_log_format(ab, " inode=%lu", ino); + if ((pino != (unsigned long)-1) || (ino != (unsigned long)-1)) + audit_log_format(ab, " dev=%02x:%02x mode=%#o" + " ouid=%u ogid=%u rdev=%02x:%02x", + MAJOR(context->names[i].dev), + MINOR(context->names[i].dev), + context->names[i].mode, + context->names[i].uid, + context->names[i].gid, + MAJOR(context->names[i].rdev), MINOR(context->names[i].rdev)); + if (context->names[i].ctx) { + audit_log_format(ab, " obj=%s", + context->names[i].ctx); + } + audit_log_end(ab); } } -/* Free a per-task audit context. Called from copy_process and - * __put_task_struct. */ +/** + * audit_free - free a per-task audit context + * @tsk: task whose audit context block to free + * + * Called from copy_process and __put_task_struct. + */ void audit_free(struct task_struct *tsk) { struct audit_context *context; - task_lock(tsk); + /* + * No need to lock the task - when we execute audit_free() + * then the task has no external references anymore, and + * we are tearing it down. (The locking also confuses + * DEBUG_LOCKDEP - this freeing may occur in softirq + * contexts as well, via RCU.) + */ context = audit_get_context(tsk, 0, 0); - task_unlock(tsk); - if (likely(!context)) return; @@ -934,13 +725,24 @@ void audit_free(struct task_struct *tsk) audit_free_context(context); } -/* Fill in audit context at syscall entry. This only happens if the +/** + * audit_syscall_entry - fill in an audit record at syscall entry + * @tsk: task being audited + * @arch: architecture type + * @major: major syscall type (function) + * @a1: additional syscall register 1 + * @a2: additional syscall register 2 + * @a3: additional syscall register 3 + * @a4: additional syscall register 4 + * + * Fill in audit context at syscall entry. This only happens if the * audit context was created when the task was created and the state or * filters demand the audit context be built. If the state from the * per-task filter or from the per-syscall filter is AUDIT_RECORD_CONTEXT, * then the record will be written at syscall exit time (otherwise, it * will only be written if another part of the kernel requests that it - * be written). */ + * be written). + */ void audit_syscall_entry(struct task_struct *tsk, int arch, int major, unsigned long a1, unsigned long a2, unsigned long a3, unsigned long a4) @@ -950,7 +752,8 @@ void audit_syscall_entry(struct task_struct *tsk, int arch, int major, BUG_ON(!context); - /* This happens only on certain architectures that make system + /* + * This happens only on certain architectures that make system * calls in kernel_thread via the entry.S interface, instead of * with direct calls. (If you are porting to a new * architecture, hitting this condition can indicate that you @@ -966,11 +769,6 @@ void audit_syscall_entry(struct task_struct *tsk, int arch, int major, if (context->in_syscall) { struct audit_context *newctx; -#if defined(__NR_vm86) && defined(__NR_vm86old) - /* vm86 mode should only be entered once */ - if (major == __NR_vm86 || major == __NR_vm86old) - return; -#endif #if AUDIT_DEBUG printk(KERN_ERR "audit(:%d) pid=%d in syscall=%d;" @@ -1014,11 +812,18 @@ void audit_syscall_entry(struct task_struct *tsk, int arch, int major, context->auditable = !!(state == AUDIT_RECORD_CONTEXT); } -/* Tear down after system call. If the audit context has been marked as +/** + * audit_syscall_exit - deallocate audit context after a system call + * @tsk: task being audited + * @valid: success/failure flag + * @return_code: syscall return value + * + * Tear down after system call. If the audit context has been marked as * auditable (either because of the AUDIT_RECORD_CONTEXT state from * filtering, or because some other part of the kernel write an audit * message), then write out the syscall information. In call cases, - * free the names stored from getname(). */ + * free the names stored from getname(). + */ void audit_syscall_exit(struct task_struct *tsk, int valid, long return_code) { struct audit_context *context; @@ -1053,7 +858,13 @@ void audit_syscall_exit(struct task_struct *tsk, int valid, long return_code) put_task_struct(tsk); } -/* Add a name to the list. Called from fs/namei.c:getname(). */ +/** + * audit_getname - add a name to the list + * @name: name to add + * + * Add a name to the list of audit names for this context. + * Called from fs/namei.c:getname(). + */ void audit_getname(const char *name) { struct audit_context *context = current->audit_context; @@ -1082,10 +893,13 @@ void audit_getname(const char *name) } -/* Intercept a putname request. Called from - * include/linux/fs.h:putname(). If we have stored the name from - * getname in the audit context, then we delay the putname until syscall - * exit. */ +/* audit_putname - intercept a putname request + * @name: name to intercept and delay for putname + * + * If we have stored the name from getname in the audit context, + * then we delay the putname until syscall exit. + * Called from include/linux/fs.h:putname(). + */ void audit_putname(const char *name) { struct audit_context *context = current->audit_context; @@ -1100,7 +914,7 @@ void audit_putname(const char *name) for (i = 0; i < context->name_count; i++) printk(KERN_ERR "name[%d] = %p = %s\n", i, context->names[i].name, - context->names[i].name); + context->names[i].name ?: "(null)"); } #endif __putname(name); @@ -1122,9 +936,52 @@ void audit_putname(const char *name) #endif } -/* Store the inode and device from a lookup. Called from - * fs/namei.c:path_lookup(). */ -void audit_inode(const char *name, const struct inode *inode, unsigned flags) +void audit_inode_context(int idx, const struct inode *inode) +{ + struct audit_context *context = current->audit_context; + const char *suffix = security_inode_xattr_getsuffix(); + char *ctx = NULL; + int len = 0; + + if (!suffix) + goto ret; + + len = security_inode_getsecurity(inode, suffix, NULL, 0, 0); + if (len == -EOPNOTSUPP) + goto ret; + if (len < 0) + goto error_path; + + ctx = kmalloc(len, GFP_KERNEL); + if (!ctx) + goto error_path; + + len = security_inode_getsecurity(inode, suffix, ctx, len, 0); + if (len < 0) + goto error_path; + + kfree(context->names[idx].ctx); + context->names[idx].ctx = ctx; + goto ret; + +error_path: + if (ctx) + kfree(ctx); + audit_panic("error in audit_inode_context"); +ret: + return; +} + + +/** + * audit_inode - store the inode and device from a lookup + * @name: name being audited + * @inode: inode being audited + * @flags: lookup flags (as used in path_lookup()) + * + * Called from fs/namei.c:path_lookup(). + */ +void __audit_inode(const char *name, const struct inode *inode, unsigned flags) { int idx; struct audit_context *context = current->audit_context; @@ -1150,15 +1007,105 @@ void audit_inode(const char *name, const struct inode *inode, unsigned flags) ++context->ino_count; #endif } - context->names[idx].flags = flags; - context->names[idx].ino = inode->i_ino; context->names[idx].dev = inode->i_sb->s_dev; context->names[idx].mode = inode->i_mode; context->names[idx].uid = inode->i_uid; context->names[idx].gid = inode->i_gid; context->names[idx].rdev = inode->i_rdev; + audit_inode_context(idx, inode); + if ((flags & LOOKUP_PARENT) && (strcmp(name, "/") != 0) && + (strcmp(name, ".") != 0)) { + context->names[idx].ino = (unsigned long)-1; + context->names[idx].pino = inode->i_ino; + } else { + context->names[idx].ino = inode->i_ino; + context->names[idx].pino = (unsigned long)-1; + } +} + +/** + * audit_inode_child - collect inode info for created/removed objects + * @dname: inode's dentry name + * @inode: inode being audited + * @pino: inode number of dentry parent + * + * For syscalls that create or remove filesystem objects, audit_inode + * can only collect information for the filesystem object's parent. + * This call updates the audit context with the child's information. + * Syscalls that create a new filesystem object must be hooked after + * the object is created. Syscalls that remove a filesystem object + * must be hooked prior, in order to capture the target inode during + * unsuccessful attempts. + */ +void __audit_inode_child(const char *dname, const struct inode *inode, + unsigned long pino) +{ + int idx; + struct audit_context *context = current->audit_context; + + if (!context->in_syscall) + return; + + /* determine matching parent */ + if (dname) + for (idx = 0; idx < context->name_count; idx++) + if (context->names[idx].pino == pino) { + const char *n; + const char *name = context->names[idx].name; + int dlen = strlen(dname); + int nlen = name ? strlen(name) : 0; + + if (nlen < dlen) + continue; + + /* disregard trailing slashes */ + n = name + nlen - 1; + while ((*n == '/') && (n > name)) + n--; + + /* find last path component */ + n = n - dlen + 1; + if (n < name) + continue; + else if (n > name) { + if (*--n != '/') + continue; + else + n++; + } + + if (strncmp(n, dname, dlen) == 0) + goto update_context; + } + + /* catch-all in case match not found */ + idx = context->name_count++; + context->names[idx].name = NULL; + context->names[idx].pino = pino; +#if AUDIT_DEBUG + context->ino_count++; +#endif + +update_context: + if (inode) { + context->names[idx].ino = inode->i_ino; + context->names[idx].dev = inode->i_sb->s_dev; + context->names[idx].mode = inode->i_mode; + context->names[idx].uid = inode->i_uid; + context->names[idx].gid = inode->i_gid; + context->names[idx].rdev = inode->i_rdev; + audit_inode_context(idx, inode); + } } +/** + * auditsc_get_stamp - get local copies of audit_context values + * @ctx: audit_context for the task + * @t: timespec to store time recorded in the audit_context + * @serial: serial value that is recorded in the audit_context + * + * Also sets the context as auditable. + */ void auditsc_get_stamp(struct audit_context *ctx, struct timespec *t, unsigned int *serial) { @@ -1170,6 +1117,15 @@ void auditsc_get_stamp(struct audit_context *ctx, ctx->auditable = 1; } +/** + * audit_set_loginuid - set a task's audit_context loginuid + * @task: task whose audit context is being modified + * @loginuid: loginuid value + * + * Returns 0. + * + * Called (set) from fs/proc/base.c::proc_loginuid_write(). + */ int audit_set_loginuid(struct task_struct *task, uid_t loginuid) { if (task->audit_context) { @@ -1188,12 +1144,59 @@ int audit_set_loginuid(struct task_struct *task, uid_t loginuid) return 0; } +/** + * audit_get_loginuid - get the loginuid for an audit_context + * @ctx: the audit_context + * + * Returns the context's loginuid or -1 if @ctx is NULL. + */ uid_t audit_get_loginuid(struct audit_context *ctx) { return ctx ? ctx->loginuid : -1; } -int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) +static char *audit_ipc_context(struct kern_ipc_perm *ipcp) +{ + struct audit_context *context = current->audit_context; + char *ctx = NULL; + int len = 0; + + if (likely(!context)) + return NULL; + + len = security_ipc_getsecurity(ipcp, NULL, 0); + if (len == -EOPNOTSUPP) + goto ret; + if (len < 0) + goto error_path; + + ctx = kmalloc(len, GFP_ATOMIC); + if (!ctx) + goto error_path; + + len = security_ipc_getsecurity(ipcp, ctx, len); + if (len < 0) + goto error_path; + + return ctx; + +error_path: + kfree(ctx); + audit_panic("error in audit_ipc_context"); +ret: + return NULL; +} + +/** + * audit_ipc_perms - record audit data for ipc + * @qbytes: msgq bytes + * @uid: msgq user id + * @gid: msgq group id + * @mode: msgq mode (permissions) + * + * Returns 0 for success or NULL context or < 0 on error. + */ +int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode, struct kern_ipc_perm *ipcp) { struct audit_aux_data_ipcctl *ax; struct audit_context *context = current->audit_context; @@ -1201,7 +1204,7 @@ int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) if (likely(!context)) return 0; - ax = kmalloc(sizeof(*ax), GFP_KERNEL); + ax = kmalloc(sizeof(*ax), GFP_ATOMIC); if (!ax) return -ENOMEM; @@ -1209,6 +1212,7 @@ int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) ax->uid = uid; ax->gid = gid; ax->mode = mode; + ax->ctx = audit_ipc_context(ipcp); ax->d.type = AUDIT_IPC; ax->d.next = context->aux; @@ -1216,6 +1220,13 @@ int audit_ipc_perms(unsigned long qbytes, uid_t uid, gid_t gid, mode_t mode) return 0; } +/** + * audit_socketcall - record audit data for sys_socketcall + * @nargs: number of args + * @args: args array + * + * Returns 0 for success or NULL context or < 0 on error. + */ int audit_socketcall(int nargs, unsigned long *args) { struct audit_aux_data_socketcall *ax; @@ -1237,6 +1248,13 @@ int audit_socketcall(int nargs, unsigned long *args) return 0; } +/** + * audit_sockaddr - record audit data for sys_bind, sys_connect, sys_sendto + * @len: data length in user space + * @a: data address in kernel space + * + * Returns 0 for success or NULL context or < 0 on error. + */ int audit_sockaddr(int len, void *a) { struct audit_aux_data_sockaddr *ax; @@ -1258,6 +1276,15 @@ int audit_sockaddr(int len, void *a) return 0; } +/** + * audit_avc_path - record the granting or denial of permissions + * @dentry: dentry to record + * @mnt: mnt to record + * + * Returns 0 for success or NULL context or < 0 on error. + * + * Called from security/selinux/avc.c::avc_audit() + */ int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt) { struct audit_aux_data_path *ax; @@ -1279,6 +1306,14 @@ int audit_avc_path(struct dentry *dentry, struct vfsmount *mnt) return 0; } +/** + * audit_signal_info - record signal info for shutting down audit subsystem + * @sig: signal value + * @t: task being signaled + * + * If the audit subsystem is being terminated, record the task (pid) + * and uid that is doing that. + */ void audit_signal_info(int sig, struct task_struct *t) { extern pid_t audit_sig_pid; @@ -1295,4 +1330,3 @@ void audit_signal_info(int sig, struct task_struct *t) } } } - |
